System and a method for joining the ends of a band-shaped elongate element

ABSTRACT

A system and method are provided for joining the ends of a bank-shaped elongate element. Alignment strips (3) are thereby fastened in the vicinity of the ends (1,2) of the elongate element, both alignment strips being formed by a sheet-like part (4) one edge of which is provided with a U-shaped element (5). In order to provide a firm joint, the alignment strips are positioned side by side so that the outer surfaces of the bottoms of the U-shaped elements (5) are in alignment. The alignment strips (3) so positioned are interlocked by means of a locking strip (7) to be passed in place from a side of the band-shaped elongate element in the longitudinal direction of the alignment strips (3) so as to be engaged with the U-shaped elements (5).

FIELD OF THE INVENTION

This invention relates to a system and a method for joining the ends ofa band-shaped elongate element and, more particularly, to a system and amethod wherein alignment strips are fastened in the vicinity of the endsof the elongate element, both alignment strips being formed by asheet-like part one edge of which is provided with a U-shaped element.

BACKGROUND OF THE PRIOR ART

Methods and systems of the above type are well-known in varioustechnical fields, for joining the ends of a band-shaped product into anendless band. Such technical fields include wood processing industriesin which endless wires and felts are used, e.g., for drying paper websin paper machines. Cellulose and paper board machines are further knownapplications.

The joining of the ends of a band-shaped product, such as a wire orfelt, is of essential importance in wood processing industries inparticular, since wires or felts woven endless are always very difficultto mount in place due to the fact that it is necessary to disassemblethe supporting structure of the rolls on one side to be able to placethe wire or felt in a paper machine, for instance. The disassembly andassembly of such structures is difficult, and plenty of room is requiredat the side of the machine as the wire or felt is mounted from the side.Furthermore, endless felts and wires are heavy and large, wherefore theyare difficult to handle.

For this reason, it is customary to weave the wire or felt into aband-shaped product the ends of which are not joined until in themachine. It is thereby possible to draw the wire or felt on the rolls inthe operating direction of the machine. Various methods and arrangementshave been developed for temporarily joining the ends of the wire or felte.g. in a paper machine After the temporary joining, a permanent jointis formed and the temporary joint is opened.

Known solutions include the method and means disclosed in SwedishPublished Specification 435,207 for joining the ends of a band-shapedproduct. This known solution utilizes a so called zipper principle,whereby ribbons are fastened adjacent to the ends of the product to formthe zipper halves The ends of the product can thereby be joined by meansof a connecting slide which functions in the same way as a conventionalzipper slide. After the forming of the temporary joint, the proper jointis formed e.g. by passing a joint thread through loops provided at theends of the product. The zipper parts are naturally removed after thepermanent joint is completed.

Another example of known solutions would be the device disclosed inFinnish Patent Application 840,804. In this known solution the ends of aband-shaped product are provided with interlocking clasp means by meansof which the ends are joined temporarily. After the temporary joint hasbeen formed in this way, the permanent joint is formed e.g. in a mannerdescribed in connection with the preceding known solution. After thepermanent joint has been formed, the clasp means are removed from theband-shaped product.

A disadvantage of these known solutions is, for instance, that thelocking of the ends of the band-shaped product may open when used as anaid in the mounting. A further disadvantage is that the adjustment isdifficult, i.e. the two sides of the joint are difficult to get properlyin alignment, wherefore the joint thread or wire is difficult to pass inplace. In addition, if the joint is not quite straight, the joining isdifficult to be carried out by means of known solutions. Also, the useof known solutions is difficult and laborious, as a result of which thechange of a felt, for instance, is slow. Prior solutions are suitablefor temporary joining only, whereby the permanent joint always has to bemade by means of different joining means.

The object of the invention is to provide a method and an arrangementfor joining the ends of a band-shaped product, which avoid thedisadvantages of the prior art. This is achieved by means of a methodaccording to the invention which is characterized in that the alignmentstrips are positioned side by side in such a way that the outer surfacesof the bottoms of the U-shaped elements are in alignment and that thealignment strips so positioned are interlocked by means of a lockingstrip to be passed in place from the side of the band-shaped product inthe longitudinal direction of the alignment strips so as to get engagedwith the U-shaped elements. An arrangement according to the invention,in turn, is characterized in that the arrangement comprises a lockingstrip provided with two members arranged to simultaneously engage withthe U-shaped elements of the alignment strips positioned side by sidewith the outer surfaces of the bottoms of the U-shaped elements inalignment, thus locking the alignment strips to each other.

An advantage of the solution according to the invention is above allthat the locking is simple as it can be effected from the side of themachine so that the locking strip automatically draws together the endsof the product. A further advantage is that the joint cannot open afterthe locking, not even when the product is loose. The invention can alsobe used for providing a permanent joint in drying felts, for instance. Araising element according to one embodiment of the invention makes iteasier to align the ends of the product and to pass the joint thread inplace, which substantially reduces the time required for the mounting ofa felt, for instance, in the machine, and expensive down times areshortened. The invention, can be advantageously applied with differentkinds of products, since the alignment strips and the locking strip canbe dimensioned according to the properties of the product to be joined.By means of the invention it is also possible to join curved ends in anextremely advantageous manner.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in the following in more detail by meansof some preferred embodiments described in the attached drawing, wherein

FIG. 1 is a general side view of a joint realization according to theinvention,

FIG. 2 illustrates another embodiment of the realization of FIG. 1,

FIG. 3 illustrates a third embodiment of the realization of FIG. 1,

FIG. 4 illustrates a fourth embodiment of the realization of FIG. 1,

FIG. 5 illustrates a fifth embodiment of the realization FIG. 1,

FIG. 6 illustrates a sixth embodiment of the realization FIG. 1,

FIG. 7 is a top view of the embodiment of FIG. 6,

FIG. 8 illustrates another embodiment of the method according to theinvention,

FIG. 9 illustrates a further application of the embodiment of FIG. 8,

FIG. 10 illustrates a further application of the embodiment of FIG. 8,

FIG. 11 is a perspective view of one preferred realization of theembodiment of FIG. 10,

FIG. 12 is a general side view of a permanent joint application of thejoint formed by means of the invention,

FIG. 13 illustrates another embodiment of the application of FIG. 12,and

FIG. 14 illustrates one possible embodiment of the locking strip.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows generally a joint formed by means of the method accordingto the invention. In the example of FIG. 1, the ends of a band-shapedproduct, such as a felt, are indicated by means of the referencenumerals 1 and 2. Alignment strips are indicated by means of thereference numeral 3 in FIG. 1. The alignment strips 3 are formed by asheet-like part 4 and a U-shaped element 5 formed to one edge of thesheet-like part 4. Further, a joint thread forming a permanent joint isindicated by means of the reference numeral 6 in FIG. 1. The jointthread 6 is passed through loops provided on the edges of the ends 1, 2.

According to the method according to the invention the alignment strips3 are fastened to the ends of the band-shaped product e.g. by sewing sothat they are positioned side by side with the outer surface of thebottoms of the U-shaped elements in alignment, i.e. the outer surfacesof the bottoms are positioned opposite to each other either in contactor at a predetermined distance from each other. The alignment strips sopositioned are interlocked by means of a locking strip 7 which is passedin place from the side of the band-shaped product in the longitudinaldirection of the alignment strips 3 so that it is engaged with theU-shaped elements 5.

In the embodiment of FIG. 1 the locking strip 7 is provided with twomembers 8 which are arranged to simultaneously engage with the U-shapedelements 5 of both alignment strips 3. In the example of FIG. 1, themembers 8 are formed by U-shaped branches, so that when the lockingstrip is pushed in place from the side of the band-shaped product, itdraws the locking strips into a position shown in FIG. 1, whereby theends 1, 2 of the band-shaped product are positioned side by side so thatthe joint thread 6 can be passed in place. The ends 1, 2 are thereby inan unstressed state, since the tensile stresses of the band-shapedproduct are transmitted through seams 9 to the alignment strips 3, whichare interlocked by means of the locking strip 7.

The length of the sheet-like parts of the alignment strips 3 in thelongitudinal direction of the product can be chosen as desired accordingto the requirements in each particular case. FIGS. 2 and 3 show twoembodiments in which the sheet-like parts 4 of the alignment strips areunequal in length. If required, the locking strip 7 can be positionedapart from the permanent joint, as is the case in the examples of FIGS.2 and 3.

The length of the sheet-like parts 4 in the longitudinal direction ofthe longitudinal element may also vary otherwise than as illustrated inthe examples of FIGS. 2 and 3. FIGS. 4 to 7 show some of theseembodiments. The sheet-like parts 4 of the alignment strips 3 maythereby be equal in size, but it is possible to attach extension plates11, 12 of desired size to the sheet-like parts 4 by means of seams 10,for example. In such embodiments the alignment strips 3 are fastenedadjacent to the ends 1, 2 by means of the seams 9 sewn in the extensionplates 11, 12 and the ends 1, 2.

The embodiments shown in FIGS. 4 and 5 differ from each other only withrespect to the position of the alignment strips 3. In the methodaccording to the invention the alignment strips 3 can be arranged in thetwo positions shown in FIGS. 4 and 5; the only essential thing is thatthe U-shaped elements should be positioned so that the outer surfaces oftheir bottoms are in alignment, as mentioned above.

The example of FIGS. 6 and 7 shows how the method according to theinvention can be applied in cases where the ends of the band-shapedproduct are not straight. The permanent joint is curved in this case. Bygiving one extension plate 11 a suitable width, the alignment strips 3can be fastened to the ends of the band-shaped product in an extremelyadvantageous manner. The extension plate 11 is thereby fastened to theend 1 by means of the seam 9 substantially parallel with the permanentjoint, and the extension plate 12 in turn by means of a straight seam9'. By means of the locking strip 7 the ends 1, 2 can be locked in aposition shown in FIGS. 6 and 7, whereby the joint thread 6 can beeasily passed in place. In FIG. 7 the reference S indicates thetemporary joint formed by the alignment strips 3 and the locking strip7.

All the above embodiments are illustrative of cases in which a temporaryjoint is made for the formation of a permanent joint. The permanentjoint is made e.g. by means of the joint thread 6. Accordingly, thealignment strips are fastened removeably to the ends 1, 2 of theband-shaped product and they are removed after the formation of thepermanent joint. Since the joining of the ends is carried out in themachine at the client factory after the band-shaped product has beendrawn into the machine, it is of advantage that the permanent joint canbe made in circumstances as advantageous as possible. Extremelyadvantageous circumstances for the formation of the permanent joint canbe obtained by raising the ends 1, 2 of the band-shaped product upwardsin the area of the locking strip 7. This can be effected e.g. by formingthe locking strip so that it acts as a part which raises the ends 1, 2of the band-shaped product. FIGS. 8 and 9 show two such embodiments. Bymeans of the embodiments of FIGS. 8 and 9 the loops used for theformation of the permanent joint can be brought into a positionextremely advantageous in view of the passing in place of the jointthread 6, so that the permanent joint can be formed rapidly.

One and the same locking strip 7 can be used e.g. in the embodiments ofFIGS. 1 and 8. In the embodiment of FIG. 8 the locking strip raising theends 1, 2 of the band-shaped product is thereby made of the lockingstrip used in the embodiment of FIG. 1 by removeably fastening aseparate raising element 13 having e.g. a triangular cross-section tothe strip. It is thereby possible to raise the ends even though thelocking strip would already have been passed in place, if it is noticedthat it would be advantageous to slightly raise the ends, e.g. in thecase of FIG. 1, irrespective of the fact that this was at firstconsidered to be unnecessary, so that the raising element was removedfrom the locking strip 7 before it was passed in place. The raisingelement 13 can thereby be inserted between the alignment strips 3 andthe ends 1, 2 of the band-shaped product in a manner shown in FIGS. 10and 11. The passing of the joint thread 6 can thereby be effected underadvantageous circumstances without having to replace the locking stripwith a strip capable of raising the ends.

Unlike the alignment strips the raising element 13 does not necessarilyhave to extend over the entire width of the band-shaped product, but itis possible to use a short raising element 13 which is displaced in thedirection of the permanent joint in proportion as the joint thread 6 ispassed in place. This is illustrated in FIG. 11 by means of the arrow N.After the permanent joint is formed, the alignment strips 3 are removedfrom the band-shaped product, whereafter the product, such as a felt, isready for operation.

The locking strip can, of course, be shaped as desired according to thespecial requirements in each particular case. FIG. 14 shows one possibleembodiment in the locking strip 7.

The method and the arrangement according to the invention can also beused for the formation of a permanent joint. Such an embodiment ispossible e.g. in connection with drying felts, whereby the joint formedby the locking strip and the alignment strips moves with the felt duringthe operation of the machine. FIGS. 12 and 13 show this type ofembodiments. The same reference numerals as in the preceding exampleshave been used in FIGS. 12 and 13 at corresponding points, since theformation of the joint as well as the means used correspond to theformation of a temporary joint described above.

The embodiments described above are by no means intended to restrict theinvention, but the invention may be modified within the scope of theclaims in various ways. Accordingly, it is obvious that the differentparts of the arrangement according to the invention do not need to beexactly similar to those shown in the figures, but other kind of partsare possible as well. The raising element 13 can be fastened removeablyto the locking strip in any suitable manner, e.g. by a snap-actionjoint, screws, U-shaped fastening means, etc. U-shaped fastening meansare particularly advantageous when a short raising element is used whichis displaced in proportion as the permanent joint is formed. The raisingelement may thereby be displaced similarly as a slide on the lockingstrip. The alignment strips and the locking strip can be made of anymaterial; advantageous results being obtained e.g. by means of plasticparts. The raising element can also be made of any suitable material,e.g. plastic or wood. The material of the extension plates, in turn, maybe rigid or soft, such as wood, plastic, metal, cloth, felt, wire etc.The alignment strips can be fastened in the area of the ends of theband-shaped product in any suitable manner, e.g. by sewing, as in theexample of the figures, or by riveting, etc.

I claim:
 1. A method for temporarily joining the ends of a band-shapedelongate element, comprising the steps of:fastening a pair of alignmentstrips each at a predetermined short distance from the respective twoends of the elongate element, both alignment strips being formed with asheet-like part one edge of which is provided with a U-shaped element,the alignment strips being positioned side by side so that the outersurfaces of the bottoms of said U-shaped elements are in alignment andthe alignment strips are positioned so as to be interlocked; passing alocking strip from one side of the band-shaped elongate element in alongitudinal direction of said alignment strips so as to engage withsaid U-shaped elements, so as to enable a permanent joint to be formedbetween said ends of said elongate element; and permanently joining saidends of said elongate element directly to each other by known means andthereafter removing said alignment strips and said locking strip fromsaid permanently joined ends.
 2. A method according to claim 1,wherein:the respective ends of the elongate element, adjacent to thecorresponding locking strips, are held away therefrom to facilitate saidstep of permanently joining said ends.
 3. Apparatus for facilitatingpermanent joining of the ends of a band-shaped elongate element into anendless band after placement of said elongate element into approximatelyits useful position in a machine suitable for processing wood orcellulose products, for use of the joined elongate element after removalof said temporarily, attached apparatus therefrom, comprising:a pair ofalignment strips, temporarily fastened at a predetermined distance fromthe respective ends of said elongate element after said placementthereof, each alignment strip being formed with a sheet-like part oneedge of which is provided with a U-shaped element having two arms one ofwhich is temporarily fastened to said elongate element and the other ofwhich lies outwardly of the elongate element such that the ends of theelongate element are disposed to make contact with each other forformation of said permanent joining thereat; and a locking stripprovided with two members, arranged to simultaneously engage with saidoutwardly lying arms of the U-shaped elements of said pair of alignmentstrips when the alignment strips are positioned side by side with theouter surfaces of bottom portions of their U-shaped elements placed inalignment for thereby temporarily locking said alignment strips to eachother so as to hold said respective ends of said elongate element incontact for permanent joining thereof by known means that permanentlyremain with said joined ends to form said endless band following removalof said alignment strips and said locking strip thereafter from saidpermanently joined ends.
 4. Apparatus according to claim 3, wherein:saidmembers of the locking strip comprise two U-shaped branches provided ontwo longitudinal side edges of the locking strip, the locking stripbeing formed to be passed in placed from one side of said elongateelement in the longitudinal direction of the alignment strips. 5.Apparatus according to claim 3, wherein:the locking strip is formed tohave a part formed and disposed to hold the ends of the elongate elementin contact with each other and away from the respective alignmentstrips.
 6. Apparatus according to claim 5, wherein:the part holding awaythe ends of the elongate element is formed by the locking strip and araising element formed to be removably attached thereto.
 7. Apparatusaccording to claim 6, wherein:said part holding away the ends of theelongate element has a generally triangular cross-section having a firstside contacting said locking strip at an outer longitudinal surfacethereof and second and third sides respectively contacting end portionsof that surface of said elongate element to which said alignment stripsare fastened such that said ends of said elongate element contact eachother at an apex formed by said second an third sides.
 8. Apparatusaccording to claim 3, wherein:said locking strip has a generally hollowtriangular section of which two sides meet at a predetermined angle toform an apex and a third side has a longitudinally aligned cut such thatsaid pair of alignment strips is engaged by said locking strip at saidcut and end portions of said elongate element are held by said two sidesto form said contact thereof at said apex.
 9. Apparatus according toclaim 3, further comprising:an end-holding element of triangular sectionhaving a base and two sides meeting at a predetermined angle to form anapex opposite said base, said end-holding element being disposed withsaid base contacting said alignment strips at an outer surface of eachaway from said locking strip engaging the same and end surface portionsof said elongate element being held by said two sides so as to make saidcontact at said apex for said permanent jointing to be formed thereat.